Process for treating artificial filaments and apparatus therefor



Sept. 6, 1938. A. HARTMANN ETAL 2,129,274

. PROCESS FOR TREATING ARTIFICIAL FILAMENTS AND APPARATUS THEREFOR 7 Filed June 14, 1934 2 Sheets-Sheet 1 Sept. 6, 1938. A. HARTMANN ET AL 2,129,274 PROCESS FOR TREATING ARTIFICIAL FILAMENTS AND APEARATUS THEREFOR' 2 Sheets-Sheet 2 Filed June 14, 1934 Patented Sept. 6, 1938 PROCESS FOR TREATING ARTIFIoIAL FILA- MnN'rs AND APPARATUSTHEREFOR August Hartman and Johannes Uy'tenbogaart,

Berlin-Lichterfelde, Germany,

assignors to North American Rayon Corporation, a corporation of Delaware Application June 14, 1934, serial No. 730,662 In Germany June 14, 1 933 6 Claims.

The invention comprises a processand apparatus for wet treatment and drying of artificial filaments or threads in the continuous process for the manufacture of artificial silk.

.5 There are already known methods according to which freshly spun artificial silk filaments which must undergo a wet treatment and a directly following drying, are led inspirals over guiding cylinders whereby they are treated with the necessary liquids for the purpose of de-acidifying, bleaching, softening, washing, etc. Such guiding cylinders have often been given the form of reels, and the spiral movement of the filaments over these guiding devices was achieved either 18 through appropriate movements of the individual laths of such a reel, or by means of guiding hooks or intermediate guiding rolls, etc. Finally it has been suggested that groups of cylinders be used in guiding the filaments, which groups should 20 be made up of two or morgcylinders, slightly sloped towardeach other, and in this manner to accomplish the spiral movement of the filament.

It has also already been suggested to treat the freshly spun artificial silk filamenton one and 25 in asecond zone on the cylinder to allow a stream of dry air to play on the cylinder, and to take effect on the filaments. Others have preferred to lead the filaments which'are to be dried over separate drying cylinders or through air drying chambers.

It is an object of this invention to provide an improved process and apparatus for the after- .treatment of artificial silk filaments, whereby the aftertreatment and drying of the filaments, while they are being passed in spirals over a rotating cylinder or a pair of rotating cylinders, are achieved in the smallest possible space.

It is a further object of the .present invention to carry out the wet treatment of freshly spun artificial filaments or threads in a continuous process while passing them in spirals over a rotating guiding device and to dry the filaments or threads on a directly following zone of the guiding device whereby the necessaryheat for the drying of the filaments is transferred from the cylinder to the filaments.

I It is another object of the "invention to transfer the heat necessary for the drying of the filaments-to the guiding device, or to a part thereof, by causing a highly heated medium to take effect directly upon such portions of the surface of the guiding device with which the windings of the filaments are not, at the moment of application of the heat, in contact.

the same cylinder, in a first zone with fluids and A still further object of the invention is a device for the wet treatment, and the immediately following drying, in a continuous process of filaments or threads which are led in spirals, whereby one or more rotating cylinders are provided as guiding and transporting means, these cylinders having, at least in the drying zone, full and fairly smooth outer surfaces, and whereby in the neighborhood of these surfaces a device is located which is adapted to transferring heat to those portions of the surfaces with which the filaments are not momentarily in contact.

' These and other objects of the present invention will become more apparent from a study of the following description and by'reference to the attached drawings in which:

Fig. 1 shows a device for wet treatment and drying of artificial filaments in side elevation in partial section; I

, Fig. 2 shows a section of the device according to, Fig. 1 in the direction of the line 2-2;'

Fig. 3 shows a similar section of a different construction of the device;

Fig. 4 shows the device of which Fig. 3 is a section, in side elevation.

Fig. 5 shows a side elevation of a further construction; I i

Fig 6 is a partial section of the side elevation of a fourth construction-form.

The present invention is based on the use of a guiding cylinder or a group of guiding cylinders, preferably of ,cylinders with a full smooth surface, at least in so far as the drying zone is concerned. Both operations, wet treatment and drying, are achieved on one and the same cylinder or rotating device or, if desirable, one and the same group of cylinders.

The wet treatment in any appropriate form is carried out on a first part of the guiding cylinder or group of guiding cylinders, i. e. by means of sprinkling; In spirally passing over the rotating device the thread reaches the drying zone and it is an important feature of the invention that in the drying zone a highly heated'medium is applied directly to that part of the cylinder or the cylinders, with which the artificial silk windings are not, at the moment of application, in contact, or with which they do not come in contact at all. The highly heated medium therefor comes directly in contact with the cylinder-walls, but as opposed to the common air-drying does not come directly in contact with the. artificial silk. t.

Especially a highly temperatured heating gas of a burning device may beused as heating methe cylinder walls. The highly heated medium, i. e. highly temperatured burning gas may be applied from within the guiding cylinder, as well as from the outside. In the first case it is most purposeful to construct the cylinder or cylinders at least in the drying zone, out of a' fireproof,

heat conducting material, such as nickel or Monel-metal or V2A=steel or similar special steels. In those cases in which the cylinder or cylinders are heated from the outside it is preferable to use fireproof materials for the cylinders, which are at the same time poor heat conductors, and it-has been found that in these cases clay 'or especially porcelain pipes or rollers are very suitable, which pipes in unglazed porous form \may be easily turned, and which are highly resistant to the temperature and temperature differences,

used in this process and are not cut by the cellu- 'lose filaments.

According to a very practical construction form two nearly parallel cylinders may be used, the axes of which however form a slight angle with one another so that the artificial silk thread, during the rotation of the cylinders is passed in 'a manner known per se in spirals over these cylinders. The wet treatments are achieved, i. e. by

--sprinkling, on the first part of .these cylinders.

The other part of the cylinder pair. is used as a drying zone. There, the highly heated medium is applied directly to the cylinder walls, however only on such portions where the highly heated medium cannot come in direct contact with the artificial silk windings, either because the .silk windings do not pass over the portions at all, or at least do not come in contact with these portions at the moment of application of the heat. It is sufficient, that one cylinder of the pair,

namely the onewhich is to be heated, is made out The heating of the cylinders in the drying zone.

from the outside may be accomplished by locating the heating medium, 1. e. burning gas, in the form of illuminating gas, water gas, generator gas, in the space between the two cylinders, near one or the other of the two cylinder surfaces with which the artificial silk does not come in contact in passing over the cylinders. In this way it is possible toapply the heat, for example, of high temperatured burning gases economically directly on the zone of the cylinder which is free of thread windings, and this heat is given up to the artificial silk windings during the continual rotation of the cylinders. This heating can, e. g.,

- be accomplished by locating gas burners with many small flames in a line along the surface, very close to the free zone of the cylinders in the drying zone. I

Instead of the common appropriate constant gas burners such devices may be used as are known in the technic of fiameless burning of iiluminating and power gases. be given a purposeful form, in that their effective surfaces are directed toward the rotating surface Such burners can' 2,129,274 dium, which maybe brought .to play directly on Y which is to be heated and for a short space conform with the surface of the cylinder, while the rest of the burner may be prevented from giving off heat rays by a suitable insulation.

The single cylinders of a guiding cylinder-pair which are at an angle to one another, maybe built alike; they may have more or less a 'constant diameter and may be built along the whole length out cf the same material. The heat which flows from the heated zone to the wet treatment zone may be used in heating the washing water and the like. That part of the cylinder which is to be used in wet treatment processes may however also be made out of a different material than that in the-drying zone, without giving up the symmetrical form of the cylinder, or this part oi the rotating cylinder may be given a difflerent the flow of heat from the drying zone to the wet treatment zone may be hindered, and for such purposes it has been found practical to put insulating discs, insulating rings, etc., consisting for example of mica or the like, between the two.

sections of the rotating cylinder.

- The invention makes it possible to simplify the apparatus and process in the continuous method of manufacturing artificial silk in a surprising manner, and to concentrate it in a small space. The possibility of the use of a high tem-- peratured heating medium, especially in the form of high temperatured burning gases on the cylinder surfaces in such a manner that the delicate artificial silk threads do not come in direct contact with the burning gases, makes it possible to dry the artificial silk economically in a continual process, and to overcome the previous difliculties in this respect. In particular in those cases where the artificial silk thread is alternately lead away from the drying cylinder and back to it again, the thread undergoes a treatment which might be called an ironing eifect, which makes the twisting and sizing unnecessary for many uses of artificial silk, because thereby the capillary filaments are pressed together to form an integral threadshaft. In the further treating of artificial silk, especially in washing, dyeing, etc., the necessary opening of the-thread again takes place.

Different construction forms which are to be used in the sense of the invention, of suitable devices are explained with reference to the drawings below.

The device for the treatment of artificial silk according to Figs. 1 and 2 is constructed of two driven treating cylinders i and 2, to which the thread is guided from a spinning device which is not shown in the drawings. The thread is guided on these cylinders in spiral windings, which is achieved by the arrangement of the cylinders at an angle to one another. The cylinders are cut off from the rest of the machine by a plate I I at the lower end in order to protect the machine from splashing water. Besides that, the water dripping off from the cylinder is led off by this The treatingliquid is applied to the cylplate. inder out of the spray tubes 3, 4. The liquid forms a thin layer around the portions of the cylinder lying below the spray tubes and fiows' can beregulated by the regulating screw 8 with a valve.

According to the construction form of Figs. 3

and 4 a surface burner is used insteadof a gas burner, it consisting of a heating plate 8 and a covering 9. In this case one is not forced to locate the heating device on the underside of the cylinder, as is necessary in the case of a gas burner, but the surface burner may be located over the lower cylinder or in any desirable position. In thisway the upper cylinder as well as the lower cylinder may be heated and the two heating devices may be connected by a connecting pipe I0, and in this case only one gas pipe is needed. The liquid is led to the upper cylinder l6 as well as to the lower cylinder I], through the pipes l3, ll, l and 28.

In Fig. 5 a device is shown in which only one treating cylinder I8 is provided which is sprinkled with liquid through pipes I9, 20, and which is heated at its upper front end by the heating device II. The left part is made out of glass; the right part out of porcelain. Between both parts is an insulation zone 21 which may consist of a narrow air layer or an intermediate layer of mica or asbestos, etc.

In order that the thread pass in regular spiral windings over the cylinder I! from the wet treatment zone .to the drying zone a free running or driven roller 2| is provided whose axes forms an angle with the axes of the roller ll. The guiding roller may be replaced by guiding hooks or by a row of little guiding rollers, etc.

Fig. 6 shows still another device, in which the heat is applied to the drying zone 23, of the cylinder 2!, from within by the heating device 24. In this case the treating-cylinder or at least its drying zone must consist, preferably, out of a substance which is a good heat conductor. In this construction the thread is guided in a spiral path by the free running little guiding rollers 25.

What we claim is:

1. In a process for the continuous manufacture of artificial filaments the steps of passing the filaments in a helical path over smooth surfaced rotating guiding surfaces, wet-treating the filaments in successive stages as they pass progressively overat least one of said surfaces, and drying the filaments in successive stages by passing them alternately a plurality of times over a heated portion of at least one of said surfaces andtoanunheatedportionofsaidaurfaeesto' which a highly heated medium has been applied at a point with which the threads are momentarily out of contact.

2.;A device for use in the manufacture of artificial silk comprising, in combination, a pair of spaced rollers, means for driving said rollers, said rollers disposed at a slight angle one to the other whereby a thread looped around said rollers will be conveyed from one end to the other, means for spraying with treating liquid one portion of said rollers, and heating means positioned between said rollers for heating a portion of at least one of the rollers.

3. A device for use in the manufacture of artificial silk comprising, in combination, a pair of spaced rotating rollers positioned at an angle one to the other whereby when thread is looped around'said rollers the said thread will be passed from one end thereof to the other end, means for spraying with treating liquid one portion of said rollers, and means positioned between said rollers and the thread passing thereover, and

means to heat a portion of the outside of at least one of said rollers, with which, at the moment of applying heat, the threads are not in contact.

5. Ina-process for the continuous manufacture of artificial filaments, the steps of passing the filaments in a helical path over smooth surfaced rotating guiding surfaces, wet-treating the filaments in successive stages as they pass progressively over at least one of said surfaces, and drying the filaments in successive stages by passing them alternately a plurality of times over a heated portion of at least one of said surfaces and an unheated portion of-said surfaces, the heated portion having applied a highly heated medium at a point with which the threads are momentarily out of contact.

6. In a process for the manufacture of artificial filaments. the steps comprising passing freshly extruded wet filaments alternately over heated and unheated surfaces a plurality of times whereby air-ironing effect of the filaments is achieved.

AUGUST HAR'IMANN. JOHANNES U'YTENBOGAART. 

